The utility of routine screening for prostate cancer with prostate specific antigen (PSA), remains highly controversial, and is not recommended by the United States Preventive Services Task Force, although it may be justified at the individual patient level. Many primary care physicians (PCPs) order PSA without helping patients understand the associated risks, benefits and downstream consequences. Shared decision-making (SDM) is an important component of high quality care which correlates with positive health outcomes, consumer demand, and a moral imperative to consider patients as persons. Ways to improve SDM include (1) "patient activation" interventions to increase patient participation in care and (2) physician interventions to improve the consultation process. We will test whether an intervention to improve SDM will improve physician and patient knowledge, skills and attitudes about PSA screening, and change PCP PSA screening practices. In a unique public-private partnership, we will recruit 145 PCPs across four health systems in California (UC Los Angeles, UC Davis, Rural Health Network, Kaiser Permanente). We will sample PCPs and patients from all major socio-demographic areas across the state. PCPs will be randomized by practice site to control (paper curriculum) or active intervention with an interactive web-based curriculum previously developed with funding from the CDC. This curriculum utilizes visual tools, video clip vignettes, and other interactive content to illustrate key points about risk assessment, PSA screening, and SDM.. In addition, patients at intervention sites will be randomized to receive either the same brochure as patients at control sites, or a further active intervention consisting of a CD-funded interactive curriculum covering similar content from a patient perspective. Both intervention groups (PCPonly or physician and patient intervention) will be compared to controls regarding knowledge, skills and attitudes. The primary endpoint will be changes in physician SDM behavior (Kaplan scale). Pre.-and post-test changes in PCP knowledge and attitudes will also be assessed, and post-intervention PCP SDM skills will be assessed using unannounced standardized patients, who present to PCP offices with a request for PSA testing. Post-test patient changes in knowledge and attitudes will also be assessed. Finally, any change in actual PSA ordering behaviors will be assessed. In summary, we will evaluate the ability of an educational intervention to improve the care of patients, both by activating/informing patients, and by providing PCPs with tools to engage patients more effectively. If proven effective, these web-based tools can be easily disseminated around the country, and internationally, to improve knowledge and attitudes about PSA screening among physicians and patients.